Ventilating-damper



. (No Model.)-

Noi. 294.773.

11.1. DORR` y VENTILAHNG DAMPLR.

Patented Mar,v 11, 1884.

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Nits rares JOHN P. DORE, OF NEENAH, WISCONSIN.

VENTILATING-DAIVI PER.

SPECIFICATION forming part of Letters Patent No. 294,773, dated March 11, 1884.

Application aimante 25, 1883. (No model.)

To LZZ whom it may concern: i

Be it known that I, JOHN P. Donn, of Neenah, in the county of Winnebago, and in the State of Wisconsin, haveinvented certain new and useful Improvements in Ventilating and other Dampers, and I do hereby declare that the following is a full, clear, and exact description thereof.V

My invention relates to dampers for ventilating rooms and regulating theV draft of Stoves, and will be fully described hereinafter.

In the drawings, Figure l is a vertical section of a stove-door embodying my invention, and Fig. 2 is a perspective view of the same. Fig. 3 is a side view of my device with the bolt turned about to hold the damper open, and Fig. 4 is a like view with the damper closed. A

A is the stove-door, which in this instance I provide with a housing, A', having front flanges, a, the upper edge of this housing being slotted at b to receive one leaf of a plate, C, which is folded or bent into'something like an inverted V, forming a sheet with two leaves, c c', the leaf c being longer than the leaf c', so that it may entirely close the opening in housing A. One edge of leaf c is notched at c, and through this notch I pass a bolt, D, into the housing, where I secure it by` riveting or otherwise. This bolt D is formed with a spiral iiange, d, on its side, and is not so tightly secured in the housing but that it may be turned, its head being milled toV give a secure hold for the ngers. The flange d extends along only a portion of the length of the bolt, there being room left forthe lowest point of the liange to pass over the leaf c', to hold it down upon the flanges of the housing when the damperis to remain closed. The spiral iange d makes only one turn about the bolt, so that when it is in engagement with the leaf c', either to hold it open or closed, a

turn'of the bolt will carry the `flange out of .the way of the leaf.

In Figs. l and 4: the damper is shown as closed, and with the inner end ofthe iiange d of bolt D resting upon its edge to keep it so.

the bolt in this position the damper is free to close entirely, but can open only as far as that portion of flange d that is in sight will permit it to. Now, when the bolt D is turned to the left, the flange d, by riding over the edge of notch c2, will force the damper down to its seat. The leaf c of .theplate O is in practice to be thrust down through a slot in the upper part of the housing, so that the plate will straddle its upper flange, and then, other things being equal, the two leaves will balance each other, and the damper will be held partly open by gravity; but if the air in the interior of the stove should be warmer than that in the room, the vacuum created would permit the outer air to close the damper; but should the outer air be of equal temperature with that in the stove, then the tendency of the two leaves to counterbalance each other would cause the leaf c to drop away from the housing and admit air to the stove. The degree of change in temperature required to affeet the plate is regulated by spreading the leaves apart or crowding them together;

The utility of my device will be appreciated when is considered the fact that if ordinary dampers are left open the draft increases with the heat of the fire, and therefore, unless the fire is watched closely, the fuel will be consumed with increasing rapidity as long as any remains, While if the damper is closed the fire will go out. Now, with iny device this cannot occur, for it is first adj usted by spreading or closing theleaves c c in such a manner that it will remain closed as long -as a predetermined temperature obtains in the stove; but as soon as the heat falls below that temperature the outer pressure of air will be insufficient to keep it closed, and it will open to admit air to increase the temperature by increasing combustion, and just as soon as the proper temperature is againreached the outer airpressure will close it again.

While I have described my device in connection with a stove, it will be equally useful in regulating the'admission of air to rooms for Ventilating them. The plates have only tobe hung over the Ventilating-openings in the walls or dues and their leaves spread apa-rt to suit the degree of temperature required. The inner leaf, c, serves in stoves, furnaces, 8mo., to prevent injury to the outer leaf, which IOO is really the damper; but beyond this it only acts as a Weighted rod would to eonnterbalance the outer leaf; and therefore, in ventilating rooms, I may dispense with this leaf and Counterbalanee the leaf c by drops, or by hanging it ont of a vertical line, or in any other suitable manner.

Having thus fully described my invention, what I elaini as new, and desire to secure by Letters Patent, is

l. As a damper for stoves, ventilators, &e., a connterbalanoed plate adapted to be hung in or over the Ventilating or dra-ft opening, in combination with means, substantially as described, for regulating and gaging its action, as set forth.

2. The damper consisting of a plate formed with two leavts bent to form an inverted V, and to be hung in or over the Ventilatingopening, as set forth.

3. The combination, with plate C, having a slotin one side, of the spirally-langed bolt D, adapted to aot upon the edges of said slot, as

'set forth.

JOHN P. DORR.

lVitnesses:

S. S. STOUT, M. KAMMHENNER. 

